Soil improver compositions such as conditioners, ameliorants and fertilizers are used to increase crop yields per hectare and to make unsuitable soils capable of supporting crops that otherwise would not have been viable.
The continued increase in crop yields and the farming of marginal soils and land has been possible by expanding and improving irrigation systems, by protecting crops from disease, insects and the competition of weeds, and by the development of new varieties of plants. An important method of improving crop yields has been achieved through the application of increasing amounts of chemical fertilizers.
The utility of chemical fertilizers is their source of nitrogen, phosphorous and potassium (NPK), and other minerals and micronutrients, in forms which are accessible to uptake by plants. Nitrogen, for example, is required in all protein, and is the most important of all plant nutrients. Nitrogenous fertilizers are often derived from ammonia, a by-product from natural gas, and whilst hazardous, gaseous ammonia can be applied under pressure to fields or more commonly ammonia is converted into urea for use as a fertilizer.
The constant assault on the land and soils by agricultural and horticultural chemicals is proving to be a major problem, causing imbalances in the amount of essential nutrients in those soils. Thus, the soils are often rendered unsuitable for economically sustained farming and at times the soils have been denatured such that normal levels of plant life cannot be supported. Furthermore, irrigation and rain water can leach applied fertilizers causing the eutrophication of lakes, rivers, and waterways, thus substantially contributing to water pollution. As the demand for increased production of foodstuffs and higher crop yields becomes greater, the pressure for wider application of chemical fertilizers becomes greater which often serves to exacerbate present levels of water pollution.
Our impact on the environment and sustainability of our soils and waterways are becoming important global issues. Governments are beginning to implement broad agricultural policies limiting the use of and at times banning chemical fertilizers, pesticides and weedicides. The leaching of chemical fertilizers has been shown to adversely effect native flora and fauna. Accumulation of phosphorous in waterways has supported the proliferation of undesirable aquatic plant growth such as blue-algae and has made conditions difficult for other plants, fish and marine organisms to survive in the highly acidified waterways.
The use of chemical fertilizers, fungicides and herbicides has paradoxically resulted in complex soil problems. The overuse of chemical fertilizers has rendered some soils toxic with unacceptably high levels of metals such as cadmium, mercury, lead, aluminium and the like, whilst also causing ionic lock-up through the use of synthetic ureas. The accumulation of aluminium salts and heavy metal salts has proven detrimental to fish and plant life. The leached nutrients assume such concentrations as to become toxic to fish and plant life and create considerable difficulties for producers who draw on poisoned water for irrigation requirements, as these toxic wastes are often growth inhibitors to many agricultural crops.
There is a need for environmentally friendly and acceptable soil improver compositions and fertilizers which are able to ameliorate soils by providing a natural source of NPK as well as other essential minerals and trace elements. It is desirable to create more favourable mediums for plant growth and to conserve soil by improving or increasing soil pH, water-holding capacity, water infiltration rates, aeration and temperature whilst being environmentally acceptable. It is also desirable to provide more or better alternatives to current soil treatments.
It is an object of the present invention to overcome or at least alleviate one or more of the above-mentioned disadvantages of the prior art.